Transport Transports Canada Canada TP 7245E



# AIRWORTHINESS DIRECTIVE

The following airworthiness directive (AD) may be applicable to an aircraft which our records indicate is registered in your na me. ADs are issued pursuant to Canadian Aviation Regulation (CAR) 521 Division X . Pursuant to CAR 605.84 and the further details of CAR Standard 625, Appendix H , the continuing airworthiness of a Canadian registered aircraft is contingent upon compliance with all applicable ADs. Failure to comply with the requirements of an AD may invalidate the flight authorization of the aircraft. Alternative means of compliance shall be applied for in accordance with CAR 605.84 and the above-referenced Standard

. This AD has been issued b y the Continuin g Airworthiness Division ( AARDG ) , National Aircraft Certification Branch, Trans p ort Canada, Ottawa, tele p hone 613 952-4357.

Pursuant to CAR 202.51 the registered owner of a Canadian aircraft shall, within seven days, notify the Minister in writing of any change of his or her name or address. To request a change of address, contact the Civil Aviation Communicat ions Centre (AARC) at Place de Ville, Ottawa, Ontario K1A 0N8 , or 1-800-305-2059 , or www.tc.gc.ca/civilaviation/communications/centre/ address.asp
2 4-0022 ( 01-2005 ) 1/2 No

. CF-2011-33 Issue Date 16 August 2011

Number: CF- 2011-33 Subject: Engine Support Beam – Cracking on the Upper and Lower Web
Effective: 31 August 2011 Applicability: Bombardier Inc. Aeroplanes: Model CL-600-1A11 (600), Serial Numbers 1004 through 1085 Model CL-600-2A12 (601 Variant), Serial Numbers 3001 through 3066 Model CL-600-2B16 (601-3A/3R Variant), Serial Numbers 5001 through 5194 Model CL-600-2B16 (604 Variant), Serial Numbers 5301 through 5665 and 5701 and subsequent. Compliance: As indicated below, unless already accomplished. Background: Cracks on the upper and lower web of t he Engine Support Beam (ESB) have been discovered on two (2) Challenger aeroplanes in service. Failure of the ESB could adversely affect the structur al integrity of the aeroplane. A Temporary Revision (TR) has been made to the Time Limits/Maintenance Checks (TLMC) manual to introduce a new Airworthiness Limitations (AWL) task to ensure that fatigue cracking of the ESB is detected and corrected.
This directive mandates the incor poration of the new AWL task.
Corrective Actions: 1. Within 60 days after the effective date of this directive, amend the Transport Canada Approved Maintenance Schedule by incorporat ing the new TLMC inspection task, as introduced per the following applicable TRs, all dated 31 May 2011:

Model TLMC Manual Chapter 5 Task Number TR Number

600 PSP 605 53-10-00-198 TR 5-151
601 PSP 601-5 53-10-00-198 TR 5-250
601-3A/3R PSP 601-5A 53-10-00-198 TR 5-261
604 CL-604 or CL-605 53-30-00-155 TR 5-2-47 or TR 5-2-9No. N ° CF-2011-33 2/2

2. Initial compliance with the above-m entioned TLMC tasks shall be carried out in accordance with the phase-in schedule as detailed in the applicable TRs. Compliance in accordance with superseding Temporary Revisions or later revisions of the Time Limits/Maintenance C hecks manual, approved by Transport Canada, also satisfies the requirem ents of this directive.
Authorization: For the Minister of Transport, Infrastructure and Communities 

### ORIGINAL SIGNED BY Derek Ferguson Chief, Continuing Airworthiness
Contact: Mr. Robert Farinas, Continuing Airworthiness, Ottawa, telephone 613-952-4357, facsimile 613-996-9178 or e-mail CAWWEBFeedback@tc.gc.ca or any Transport Canada Centre.